Influence of membrane morphology on humic acid removal behavior of adsorptive membrane by embedding modified montmorillonite |
Author : Elham Shokri; Reza Yegani |
Abstract | Full Text |
Abstract :In this study the efficiency of two different morphologies of polysulfone adsorptive membranes was examined for the humic acid removal from contaminated water. Adsorptive membranes with finger-like and sponge-like pore structures were prepared using modified montmorillonite with amino acid. Structure of fabricated membranes was investigated by Field Emission-Scanning Electron Microscopy, pure water flux, porosity and contact angle measurement. The obtained results showed that the addition of modified montmorillonite (MMT) to the membrane with finger-like structure altered the morphology and improved pure water flux, porosity and hydrophilicity. These changes were negligible in PSf with sponge-like structure. In addition, the adsorption property of these membranes for the removal of humic acid (HA) was extensively studied. Adsorption capacity of cellular membrane was higher than the finger-like structure and Freundlich isotherm model was ?tted for both of them. Nevertheless, the membrane with finger-like pores provides rapid adsorption of HA respect to cellular structure. It was also found that increasing the pH until pH=8 enhanced HA removal for adsorptive membranes, but increasing the pH above this point was not favorable. The obtained results from the dynamic adsorption revealed that sponge-like and finger-like membranes could generate 100 mL and 50 mL permeate of high quality (<1 ppm HA in water), respectively. |
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Decontamination study of Organic Pollutants from wastewater for Sustainable Clean Environment |
Author : Ganesh Jethave; Umesh Fegade; Sanjay Attarde; Sopan Ingle |
Abstract | Full Text |
Abstract :The successful synthesis and characterization of AlTiPbO Nanoparticles (ATPO-NPs) using a facile and straight forward co-precipitation method was reported in the present work. The detailed morphological characterization uncovered that the nanoparticles are of 28 nm in size. From the application perspective, the nanoparticles were utilized as a potential adsorbent to remove the toxic and hazardous dye from the aqueous phase. The point by point adsorption studies uncovered that the AlTiPbO nanoparticles made the Eriochrome black-T solution becomes colorless within 90 min. The outcome of the study verified by isotherms and kinetic study measurements and the adsorption system was examined. The nanoparticles have been effectively reused up to fifth cycle of the adsorption. A real sample analysis study revealed that ATPO-NPs could remove high concentrations (1000 mg/g) of dye from the industrial waste sample. |
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Nitrogen doped porous carbon derived from nanofibrous polyaniline for CO2 adsorption |
Author : Soodabeh Khalili; Mohsen Jahanshahi |
Abstract | Full Text |
Abstract :The objective of this work is to develop a cost-effective carbonaceous CO2 adsorbent. N-doped porous carbon (NDC) with nano- pore size was synthesized by KOH activation of nano polyaniline (PANI). PANI synthesized in this work has thin nanofibrillar morphology with di?erent lengths and diameters. The activation process was carried out at 800 °C with KOH/precursor ratio of 2. This adsorbent of carbon exhibits high CO2 adsorption capacity of 1.9 mmol/g at 25 °C under atmospheric pressure. The morphology of PNCs is investigated through different technical methods, such as scanning electron microscopy (SEM), N2 adsorption isotherm at 77 K and Fourier transform infrared spectroscopy (FTIR). The CO2 adsorption experiments were done at three different temperatures (298, 308, and 318 K) and pressures up to 10 bar, and correlated with the Langmuir, Freundlich, and Sips models. The Sips isotherm model presented the best fit to the experimental data. Small values of isosteric heat of adsorption were evaluated based on Clausius–Clapeyron equation showed the physical nature of adsorption mechanism. The high amount of CO2 capture by nano- pore size NDC renders it as a promising carrier for practical applications such as gas separation. |
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. Application of wet chemical surface functionalization method in preparation of anti-fouling polysulfone microporous membrane for water treatment |
Author : Milad Fonouni; Habib Etemadi; Reza Yegani; Masoumeh Safary Dehnavi; Naeime Jodeiry |
Abstract | Full Text |
Abstract : In this work, KClO3, K2Cr2O7 and KMnO4, dissolved in sulfuric acid, were used to functionalize microporous Polysulfone (PSf) membranes; fabricated by phase inversion method. The optimum concentrations of oxidizing agent and sulfuric acid and membrane immersion times were determined. FTIR results revealed that the absorbance intensities of -OH and C=O peaks as well as the variety of functional groups in the samples treated by KClO3 are remarkably higher than in the samples treated by K2Cr2O7 and KMnO4, respectively. Bovine serum albumin (BSA) filtration experiments revealed that the total fouling ratio (TFR) and irreversible fouling ratio (IFR) decreased from 73.4% for pristine PSf membrane to 52.9%, 49.4% and 60.4% for treated membranes by Set A (K2Cr2O7), Set B (KClO3) and Set C (KMnO4), respectively. Moreover, IFR of membranes decreased from 45.4% for pristine PSf membrane to 29.9%, 22.4% and 36.1% for treated membranes by Set A, Set B and Set C, respectively. |
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Effect of dosage and particle size of natural zeolite on the survival of Escherichia coli in soil |
Author : Ali Akbar Safari Sinegani; Omid Noroozi |
Abstract | Full Text |
Abstract :Survival of enteropathogenic bacteria in soil is a key factor to control waterborne diseases. The significance of zeolite nanoparticles in comparison with natural size particles on the survival of Escherichia coli in soil was studied in sterile and unsterile conditions. The experimental mixtures prepared by adding zeolite and nanozeolite at levels of 0, 5, 15% w/w to a loam textural soil to obtain 100 gr mixtures. Mixtures inoculated by a nalidixic acid resistance Escherichia coli (E.coli NAR) at a rate of 106 cells gr-1 soil. |
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Investigation and Comparison of Fluoride Adsorption Behavior on a Hybrid Material Containing Zirconium Dioxide Coated on ?-Alumina (60 and 90) and Their Initial Precursor in Aqueous Solution |
Author : Ramin Yavari |
Abstract | Full Text |
Abstract :In the present research work, zirconium oxide coated on activated alumina (Al2O3-90, Al2O3-60) were synthesized and used along with their pristine materials to investigate and compare the adsorption behavior of fluoride on them. These material was characterized by BET and X-ray diffraction analyzer. The obtained results confirmed that the immobilization of ZrO2 particles on the external surface pore of Al2O3-60 and Al2O3-90 has been performed successfully. The results of adsorption behavior study show that among these adsorbents, the synthesized hybrid material “Al2O3-60-ZrO2” has high affinity toward the adsorption of fluoride ions from aqueous solution under ambient condition (36.62 mg.g-1). Adsorption data in all of adsorbents were fitted with Langmuir model and the calculated E value shows that the chemical sorption process is a dominant mechanism in adsorption process. In the first 80 minutes of contact time, the maximum adsorption of fluoride was found to be for these synthesized hybrids” Al2O3-60-ZrO2, Al2O3-90-ZrO2”. The adsorption rate of fluoride ions on these hybrid materials in spite of their initial material was almost independent on pH value in the range 3 to 8. The negative values of ?G° indicates that the adsorption process of fluoride ions onto these adsorbents is exergonic and will proceed spontaneously. In addition, overall, the obtained results show that the prepared hybrid materials as adsorbents are promising and potential candidate for the adsorption and removal of trace amount of fluoride from nuclear and chemical wastewater. |
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Sonocatalyst efficiency of palladium-graphene oxide nanocomposite for ibuprofen degradation from aqueous solution |
Author : Atiyeh Yazdani; Mohammad Sayadi; ava Heidari |
Abstract | Full Text |
Abstract :Worldwide studies on contamination levels of anti-inflammatory drugs such as ibuprofen (IBF) show that their concentration in water bodies is increasing. Graphene oxide/palladium nanoparticle (Pd NPs-GO) was synthesized via a simple solvothermal method. The characteristics of the as-prepared samples were examined using X-ray fluorescence, scanning electron microscopy, and Fourier transforms infrared spectroscopy. The performance of Pd NPs-GO nanocomposite as a sonocatalyst was evaluated for the degradation of IBF under ultrasonic irradiation (35 kHz), and compared with graphene (GO) and palladium nanoparticle (Pd NPs). Some influencing parameters such as IBF initial concentration, pH, catalyst dosage, and irradiation time were investigated. The findings showed that Pd NPs-GO nanocomposite exhibited higher sonocatalyst activity for IBF than other catalysts. A higher ibuprofen degradation efficiency was observed in lower pH (3), lower initial concentration (30 mg/L), higher catalyst dosage (2 g/L), and higher ultrasonic irradiation time (50 min). The kinetics of the degradation of IBF followed pseudo-first-order reaction kinetics. |
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Effect of Chitosan Nano-Gel/Emulsion Containing Bunium Persicum Essential Oil and Nisin as an Edible Biodegradable Coating on Escherichia Coli O157:H7 in Rainbow Trout Fillet |
Author : Hamidreza Kazemeini; Asghar Azizian; Mohammad Hassan Shahavi |
Abstract | Full Text |
Abstract :This research aimed to assess the effect of biodegradable coating chitosan nano-gel/emulsion loaded by Bunium persicum essential oil and nisin on E. coli O157:H7 in rainbow trout fillet during 12 days at refrigeration (4°C). Trout fillet Sample was divided into 6 groups after inoculation of bacteria (E. coli O157:H7), including control (without any coating), coated with chitosan 2% and other groups including nano-emulsion chitosan 2%, Nano-emulsion of chitosan containing Bunium persicum essential oil (0.5%), Nano-gel of chitosan containing nisin (200 IU/g) and Nano-gel/emulsion of chitosan containing Bunium persicum essential oil (0.5%) and nisin (200 IU/g). The samples were stored at the cool condition, and the bacterial count was performed on days: 0, 1, 2, 4, 8, and 12. The mean number of the bacterial count was significantly different among treatment (p<0.001). The most significant inhibitory effect on the growth of E.coli O157:H7 was observed in chitosan Nano-emulsion coating containing Bunium persicum essential oil (0.5%) and nisin (200 IU/g). According to this study, it was concluded that the use of Nano-gel/emulsion of chitosan coating Bunium persicum essential oil and nisin could be effective on the decrease of E.coli O157:H7 growth in food. |
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